Investigating the association between smoking cessation and mental health in people with and without psychiatric disorders

Lead Investigator: Angela Wu, University of Oxford
Title of Proposal Research: Investigating the association between smoking cessation and mental health in people with and without psychiatric disorders
Vivli Data Request: 6544
Funding Source: Angela D Wu is funded by Nuffield Department of Primary Care Health Sciences through a grant received by the British Heart Foundation. Prof. Paul Aveyard is an NIHR senior investigator and funded by NIHR Oxford Biomedical Research Centre and NIHR Oxford Applied Research Collaboration. Dr. Gemma Taylor is funded by a Cancer Research UK Postdoctoral Fellowship (C56067/A21330).
Potential Conflicts of Interest: None

Summary of the Proposed Research:

In many countries, such as the United Kingdom, the prevalence of smoking in the general population has decreased from approximately 46% in 1970s to 14.9% in 2018. The decrease in prevalence is not to the same extent among people with mental health conditions, with the prevalence remaining at around 40% from 1993 to 2013. Many individuals who smoke say that they wish to quit; however, many continue to believe that smoking provides them with mental health benefits. This belief is shared among individuals with and without psychiatric disorders. Smokers, therefore, may be less likely to cease smoking if they believe that their mental health will decline as a result. Additionally, health professionals may also thereby be reluctant to suggest smoking cessation to certain smokers due to impact on mental health. However, there is evidence suggesting that there is an association between stopping smoking and improved mental health. Given that the rate of smoking in individuals diagnosed with psychiatric disorders is not subsiding to the same level as the general population, it is, therefore, essential to update the evidence exploring the association between mental health and smoking for populations with and without psychiatric disorders.

This project’s focus is to assess the strength of the relationship between quitting smoking and increased positive mental health for people with and without psychiatric disorders. It is not feasible to randomly assign participants to continue or quit smoking; therefore, to study the association between smoking cessation on mental health, observational analysis strategies must be used. The primary issue with traditional observational epidemiology is teasing out whether associations are causal. This study will have a unique opportunity to use three analytical approaches in a large dataset with populations with and without psychiatric disorders in order to derive results with higher causal inference confidence. We will triangulate results derived from statistical methods that differ in their ability to produce causal estimates: multivariable regression models, propensity score-adjusted models, and instrumental variable regressions.

Requested Studies:

Evaluating The Safety And Efficacy Of Varenicline and Bupropion For Smoking Cessation In Subjects With And Without A History Of Psychiatric Disorders (EAGLES)
Data Contributor: Pfizer
Study ID: NCT01456936